Adobe Photoshop CS4 - Manual (Page 268)

261 USING PHOTOSHOP CS4
Selecting and masking
Last updated 1/10/2010
Before manually adding to or subtracting from a selection, you may want to set the feather and anti-aliasing values in
the options bar to the same settings used in the original selection.
Add to a selection or select an additional area
1 Make a selection.
2 Using any selection tool, do one of the following:
• Select the Add To Selection option in the options bar, and drag to add to the selection.
• Hold down Shift, and drag to add to the selection.
A plus sign appears next to the pointer when you’re adding to a selection.
Subtract from a selection
1 Make a selection.
2 Using any selection tool, do one of the following:
• Select the Subtract From Selection option in the options bar, and drag to intersect with other selections.
• Hold down Alt (Windows) or Option (Mac OS), and drag to subtract another selection.
A minus sign appears next to the pointer when you’re subtracting from a selection.
Select only an area intersected by other selections
1 Make a selection.
2 Using any selection tool, do one of the following:
• Select the Intersect With Selection option in the options bar, and drag.
• Hold down Alt+Shift (Windows) or Option+Shift (Mac OS) and drag over the portion of the original selection that
you want to select.
An “x” appears next to the pointer when you’re selecting an intersected area.
Intersected selections
Expand or contract a selection by a specific number of pixels
1 Use a selection tool to make a selection.
2 Choose Select > Modify > Expand or Contract.
3 For Expand By or Contract By, enter a pixel value between 1 and 100, and click OK.
The border is increased or decreased by the specified number of pixels. Any portion of the selection border running
along the canvas’s edge is unaffected.